Getting weird error message

[Tom Cruickshank]

Hello,
      I'm a real newbie at getting IMP to work and I have 
installed/configured imp 2.3.6 on my server with
the latest hrode version from CVS. I have followed the very detailed 
instructions provided in /horde/docs/INSTALL
and almost have everything working. Whenever I go to 
http://www.server.com/horde/imp/login.php I keep getting
this error message.

Fatal error: Undefined class name 'log' in 
/home/httpd/html/horde/imp/login.php on line 53 .

It was showing me another error message when I first started, but I created 
a emply file called Log.php in /usr/local/lib/php
(was that the right thing to do?)

Also, is there a certain method beyond the /horde/docs/INSTALL that I need 
to use to configure imp?

Any help would be deeply appreciated! Thanks!

Sincerely,

Tom Cruickshank